Flexible sheath assemblies and interventional catheter systems incorporating them

Abstract

Sheath assemblies incorporating slotted structures at one or more areas provide areas of different flexibility and bendability characteristics along the length of the sheath assembly. An inner tubular member has an arrangement of discontinuous slots along at least a portion of its length, with at least some of the slots terminating in an enlarged aperture at at least one terminus of the slot, and a flexible outer tubular member contacts and extends over at least a portion of the inner tubular member.

We claim: 
     
       1. A medical device comprising:
 a sheath assembly including a lumen and an inner tubular member having a plurality of discontinuous slots along at least a portion of its length, wherein the plurality of slots includes a first slot having an enlarged aperture at a terminus and a flexible outer tubular member contacting and extending for at least a portion of the length of the inner tubular member; 
 a rotatable drive shaft disposed along the lumen, wherein the drive shaft includes a distal end region and a proximal end region; 
 a rotatable operating head coupled to the distal end region of the drive shaft; and 
 a control console coupled to the proximal end region of the drive shaft. 
 
     
     
       2. The medical device of  claim 1 , wherein the inner tubular member has a plurality of sections having different arrangements of discontinuous slots along the length of at least two sections. 
     
     
       3. The medical device of  claim 2 , wherein the inner tubular member has a plurality of sections having different lengths of discontinuous slots along the length of at least two sections. 
     
     
       4. The medical device of  claim 3 , wherein at least one of the sections has slots having different slot lengths neighboring one another. 
     
     
       5. The medical device of  claim 2 , wherein at least one of the sections has slots with slot lengths that vary over the length of the section, the slot lengths transitioning in a graduated fashion from a shorter length to a longer length. 
     
     
       6. The medical device of  claim 2 , wherein the inner tubular member has a plurality of sections having different patterns of discontinuous slots along the length of at least two sections. 
     
     
       7. The medical device of  claim 1 , wherein the first slot has a second aperture at a second terminus. 
     
     
       8. The medical device of  claim 1 , wherein the first slot has a slot width and the enlarged aperture has an aperture width, and wherein the aperture width is at least twice the slot width. 
     
     
       9. The medical device of  claim 1 , wherein the first slot has a slot width and the enlarged aperture has an aperture width, and wherein the aperture width is at least 4 times the slot width. 
     
     
       10. The medical device of  claim 1 , wherein the at least some discontinuous slots extend for a length greater than the circumference of the inner tubular member. 
     
     
       11. The medical device of  claim 1 , wherein the at least some discontinuous slots extend for a length greater than 360° around the circumference of the inner tubular member. 
     
     
       12. The medical device of  claim 1 , wherein the at least some discontinuous slots extend for a length greater than 180° around the circumference of the inner tubular member and less than the circumference of the inner tubular member. 
     
     
       13. The medical device of  claim 1 , wherein slot termini, or enlarged apertures provided at slot termini, are separated from neighboring slot termini or enlarged apertures by unslotted regions extending for a length of less than 90° around the circumference of the inner tubular member. 
     
     
       14. The medical device of  claim 1 , wherein the inner tubular member comprises at least two tubular sections arranged end-to-end and joined to one another. 
     
     
       15. The medical device of  claim 14 , wherein the tubular sections have different diameters. 
     
     
       16. A catheter system comprising the medical device of  claim 1 , wherein the operating head is connected, directly or indirectly, at a distal end of the sheath assembly. 
     
     
       17. A catheter system of  claim 16 , wherein the operating head rotates independently of and traverses the sheath assembly coaxially. 
     
     
       18. A catheter system of  claim 16 , additionally comprising a control component associated with the control console.